Deck 6: Wireless Lans I

Question 1

Wireless network standards are ________ standards.

A)OSI
B)TCP/IP
C)both A and B

Answer 1

A

Question 2

What propagation problem is especially bad in moist air?

A)absorptive attenuation
B)electromagnetic interference
C)multipath interference
D)inverse square law attenuation

Answer 2

A

Question 3

Signals in a transmission usually ________.

A)travel at a single frequency
B)spread over a range of frequencies
C)spread over the entire frequency distribution
D)spread over the entire service band

Answer 3

B

Question 4

A cellular telephone uses a(n)________.

A)omnidirectional antenna
B)dish antenna
C)both A and B
D)neither A nor B

Question 5

The most serious problem with wireless transmission in WLANs is ________.

A)inverse square law attenuation
B)absorptive attenuation
C)shadow zones
D)multipath interference

Question 6

Frequency is measured in terms of ________.

A)nanometers
B)hertz
C)microns
D)microseconds

Question 7

Wireless network standards operate at ________.

A)the data link layer
B)the Internet layer
C)both A and B
D)neither A nor B

Question 8

Compared to wired transmission,propagation problems in radio transmission are ________.

A)worse
B)about as bad
C)better

Question 9

What propagation problem becomes worse as frequency increases?

A)inverse square law attenuation
B)electromagnetic interference
C)both A and B
D)neither A nor B

Question 10

Wireless radio transmission speed is usually measured in terms of ________.

A)wavelength
B)frequency
C)amplitude
D)wetness

Question 11

We use the terms Wi-Fi and ________ interchangeably in this book.

A)802.1
B)802.3
C)802.11
D)802.1X

Question 12

Wi-Fi Standards come from the ________ Working Group.

A)802.1
B)802.3
C)802.11
D)802.1X

Question 13

At 10 meters,a signal has a strength of 100 mW.About how strong will it be at 40 meters?

A)about 0.5 mW
B)about 5 mW
C)about 25 mW
D)about 6 mW

Question 14

What propagation problem becomes worse as there is a large and dense object between sender and receiver?

A)multipath interference
B)shadow zones or dead zones
C)both A and B
D)neither A nor B

Question 15

Radio transmission is measured in terms of ________.

A)bytes per second
B)wavelength
C)frequency
D)bits per second

Question 16

The frequency spectrum extends ________.

A)into the gigahertz range
B)into the visible light range
C)into the ultraviolet range
D)to infinity

Question 17

The other wireless device is far away in a known direction.It would be better to use ________.

A)an omnidirectional antenna
B)a dish antenna
C)neither A nor B

Question 18

2.4 GHz and 5 GHz are ________.

A)frequency spectrums
B)broadbands
C)channels
D)service bands

Question 19

Wireless access points typically link wireless clients to ________.

A)wireless servers
B)servers on the wired network
C)both A and B

Question 20

To handle multiple conversations in radio transmission,you normally use multiple ________.

A)channels
B)frequencies
C)service bands
D)wires

Question 21

A single access point and the set of hosts it serves is called a(n)________.

A)BSS
B)BSSID
C)ESS
D)none of the above

Question 22

To connect to an access point,you must know its ________.

A)SSID
B)EUI-48 address
C)IP address
D)Wi-Fi ID

Question 23

To transmit very rapidly in RADIO,you need ________.

A)single-frequency transmission
B)single-mode transmission
C)wide bandwidth
D)narrow bandwidth

Question 24

A wireless host sends a packet to a server on the company's wired Ethernet LAN via an access point.How many frames will be involved in this one-way transmission?

A)1
B)2
C)4
D)There will be one frame for each switch along the way.

Question 25

Channels with wide bandwidths are called ________ channels.

A)multimode
B)full-duplex
C)broadband
D)parallel

Question 26

To transmit data very rapidly,you would want a ________ channel.

A)narrowband
B)broadband
C)single-frequency band
D)none of the above

Question 27

A channel extends from 55 MHz to 60 MHz.Its bandwidth is ________.

A)60 MHz
B)55 MHz
C)65 MHz
D)none of the above

Question 28

The 2.4 GHz band supports ________ possible non-overlapping 20 MHz channel(s).

A)1
B)3
C)7
D)11

Question 29

Spread spectrum transmission is used in WLANs for ________.

A)higher transmission speed
B)more reliable transmission
C)greater security
D)more efficient transmission

Question 30

802.11 standards are being developed to work in the ________ unlicensed band.

A)2)4 GHz
B)5 GHz
C)both A and B
D)neither A nor B

Question 31

WLANs normally use ________.

A)licensed bands
B)unlicensed bands
C)both A and B
D)neither A or B

Question 32

Access points take ________ from wireless devices and send them on to devices on the wired LAN.They also do the converse.

A)packets
B)frames
C)both A and B
D)neither A nor B

Question 33

To use an access point,you need to know its ________.

A)SSID
B)BSSID
C)ESSID
D)Wi-Fi ID

Question 34

A channel has more bandwidth than is necessary given data transmission speeds requirements in ________ transmission.

A)normal radio
B)reliable commercial
C)spread spectrum
D)licensed

Question 35

Which of the following uses OFDM?

A)802.11ac
B)802.11n
C)both A and B
D)neither A nor B

Question 36

Companies are moving to the 5 GHz band because there is ________ than in the 2.5 GHz band.

A)more bandwidth
B)less absorptive attenuation
C)both A and B
D)neither A nor B

Question 37

The 5 GHz band usually supports about ________ non-overlapping 20 MHz channel(s).

A)1
B)3
C)7
D)12

Question 38

In unlicensed bands,________.

A)you can use radios wherever you please
B)you can prevent nearby businesses from setting up access points in the same channel
C)both A and B
D)neither A nor B

Question 39

________ have SSIDs.

A)Wireless clients
B)Wireless access points
C)both A and B
D)neither A nor B

Question 40

Spread spectrum transmission is used in WLANs because ________.

A)it is required by regulators
B)it offers strong security
C)both A and B
D)neither A nor B

Question 41

________ is a technique for preventing two wireless stations from transmitting at the same time and therefore interfering with each other.

A)Creating extended service sets
B)Roaming
C)The distribution system
D)Media access control

Question 42

CSMA/CD+ACK is ________.

A)unreliable
B)reliable
C)semireliable

Question 43

Wider channel bandwidth ________.

A)increases transmission speed
B)allows more channels to be used in a service band
C)both A and B
D)neither A nor B

Question 44

An extended service set (ESS)is a group of BSSs that ________.

A)are connected to the same distribution system
B)have the same SSID
C)both A and B
D)neither A nor B

Question 45

In CSMA/CD+ACK,when a wireless NIC wishes to transmit,it listens for traffic.If there is traffic,it waits.When the traffic stops,it may transmit immediately.

A)always true
B)sometimes true
C)always false

Question 46

In the 5 GHz band,how many channels can you have with 802.11ac with 80 GHz channels?

A)1
B)6
C)12
D)24

Question 47

In an extended service set,each access point ________.

A)must have the same SSID
B)must have different SSIDs
C)must have coordinated SSIDs
D)none of the above

Question 48

The 802.11 standard has two mechanisms for media access control.One of two mechanisms is mandatory; it is ________.

A)MAC
B)CSMA/CA+ACK
C)RTS/CTS
D)CSMA/CD

Question 49

Which of the following is the newest Wi-Fi standard?

A)802.11ac
B)802.11g
C)802.11n
D)802.11b

Question 50

CSMA/CA+ACK usually is ________.

A)mandatory
B)optional
C)not important
D)efficient

Question 51

Media access control governs transmission by ________.

A)access points
B)wireless hosts
C)both A and B
D)neither A nor B

Question 52

Today,Wi-Fi sales are dominated by ________.

A)802.11a
B)802.11g
C)802.11n
D)802.11ac

Question 53

Access points in the same ESS communicate via ________.

A)wireless transmission
B)the distribution system
C)a master access point
D)routers

Question 54

Which of the following is more efficient and faster?

A)CSMA/CA+ACK
B)RTS/CTS
C)Both are about equally efficient and fast.

Question 55

Which of the following only operates in the 5 GHz band?

A)802.11b
B)802.11ac
C)802.11g
D)802.11n

Question 56

In 802.11g,channel bandwidth usually is ________.

A)20 GHz
B)40 GHz
C)20 MHz
D)40 MHz

Question 57

What happens if two nearby access points use the same channel?

A)They will interfere with each other.
B)They will be bonded for joint operation automatically.
C)They will be bonded for joint operation automatically if they are on the same ESS.
D)They will be bonded for joint operation automatically if they have the same SSID.

Question 58

The standard for roaming among access points is ________.

A)802.11r
B)802.11s
C)802.11W
D)the wireless handoff protocol

Question 59

In ________,when a wireless host wishes to send,it first sends a message to the wireless access point asking for permission to send.When the access point sends back a response,the host sending the original message may transmit.All other hosts must wait.

A)CSMA/CA+ACK
B)CSMA/CA
C)CSMA/CD
D)RTS/CTS

Question 60

There is an access point that serves eight wireless hosts.On how many channels will these devices transmit and receive during the course of an hour or two?

A)1
B)2
C)8
D)9

Question 61

MIMO ________.

A)bonds two or more channels for higher speed
B)is used in all forms of 802.11
C)uses a single spatial stream but multiple signals
D)transmits multiple signals in the same channel

Question 62

MIMO ________.

A)increases throughput
B)lowers propagation distance
C)both A and B
D)neither A nor B

Question 63

If an 802.11n client tries to use an 802.11ac access point,________.

A)they will not be able to communicate
B)they will communicate using 802.11n
C)they will communicate using 802.11ac
D)either B or C

Question 64

Mesh networking in 802.11 is likely to use ________.

A)only wireless devices
B)wireless devices and the site's wired LAN
C)both A and B

Question 65

The 802.11 standard for mesh networking is ________.

A)802.11m
B)802.11r
C)802.11ac
D)802.11s

Question 66

Beamforming can allow an access point to ________.

A)direct power to individual clients
B)send signals to two different clients at the same time
C)both A and B
D)neither A nor B

Question 67

An access point can transmit to more than one wireless client at a time with ________.

A)bonding
B)MIMO
C)Multiuser MIMO
D)CSMC/CA+ACK

Question 68

If two products both comply with 802.11 ac,they should have close to the same performance.

Question 69

If more users move to an access point,this decreases ________.

A)individual throughput
B)aggregate throughput
C)both A and B
D)neither A nor B